Pressure and WInds

Isobars

lines of equal pressure

Sea-Level Pressure (SLP)

pressure that would exist if stations were located at sea level

Horizontal Pressure Gradient

rate if change in atmospheric pressure between two areas

Thermal Low

hot surface causes air to rise, therefore lower pressure

Thermal High

cold surfaces cause air to sink, therefore higher pressure

Dynamic Low

air diverges in upper atmosphere causing air to be pulled up from the surface

Dynamic High

air converges in the upper atmosphere, then forces air down to the surface